About 80% of 51 recently extinct hooved mammals were probably migratory, against 46% of living species, but the fossil-based model that links migration to higher extinction rates flips direction when extinct species are left out.
Peer reviewed · Phylogenetic modelling · Migration in extinct species is inferred, not observed
Joel Abraham of Princeton University and colleagues report in PLOS Biology (5 November 2026) that migratory hooved mammals have gone extinct more often than non-migratory ones. Of 51 ungulate species lost in the late Quaternary, about 41 were likely migratory. The catch is that the migratory label for those extinct animals was imputed from body mass, diet and latitude, and the extinction-rate result only appears when fossil species are included in the models.
What you need to know
- Finding: About 80% of 51 extinct late Quaternary ungulates (41 by the median reconstruction) were likely migratory, compared with 46% (95 of 207) of living ones.
- Method: The team imputed migration for extinct species from body mass, grass in the diet and latitude, then fitted diversification models (HiSSE) across 100 versions of an evolutionary tree.
- Source: Abraham et al., PLOS Biology, 5 November 2026, open access.
- Why it matters: If migration really raises long-term extinction risk, modern migrations already under pressure from fences, roads and hunting may be especially fragile.
- Limitation: Only 10 of 16 extinct species with fossil evidence matched their imputed status, and extant-only models gave a weaker, partly opposite extinction result.
Evidence at a glance
| Item | Assessment |
|---|---|
| Evidence status | Peer reviewed; comparative phylogenetic analysis with imputed traits; correlational, not experimental. |
| Primary source | Abraham J.O., O’Brien K., Upham N.S., Jesmer B.R., Bibi F., Faith J.T., “Phylogenetic evidence that migratory behavior increases ungulate extinction rates”, PLOS Biology, published 5 November 2026, DOI 10.1371/journal.pbio.3004072. Release: EurekAlert. |
| Evidence strength | Limited to moderate. The 80% versus 46% contrast is a clear pattern, but it rests on inferred migration, and the authors report that the rate estimates depend strongly on whether fossil species are included. |
| Principal limitation | Migration was not observed in most extinct species; it was predicted from three traits, and the extinction-rate result reverses direction in living-species-only models. |
| Coverage at a glance | Independent count: Not assessed. As of 6 November 2026, 10:16 UTC, SciQuest found the PLOS release (via EurekAlert) and a Phys.org repost of it, and no independent reporting with its own writing. Reposts were not counted. |
Sources: the paper and a SciQuest search of coverage on the observation date. Coverage count is not evidence the result is correct.
Is this a big deal?
A useful, carefully hedged step rather than a verdict. The pattern is striking, and the authors are open about its weak points. Treat it as a hypothesis with fossil support: migration may have been a risky strategy for hooved mammals, and the evidence is not yet strong enough to say it was.
What scientists found
Ungulates are hooved mammals such as deer, antelope and wildebeest. The team compared 51 extinct species with 207 living ones. For the extinct group, 41 (median; range 39 to 42 across tree versions) were reconstructed as migratory, which is about 80%. Among living species, 95 of 207 (46%) migrate. That is a gap of roughly 34 percentage points.
Africa shows the same lean. There, 13 to 16 of 18 extinct species (72% to 89%) were migratory, against 33 of 93 living species (36%).
The diversification models then asked whether migratory lineages split into new species and die out faster. In the fossil-inclusive HiSSE analysis, migratory lineages had an estimated speciation rate of 2.825 per lineage per million years versus 1.673 for non-migratory lineages (about 1.7 times higher). Their extinction rate was 2.603 versus 1.486, about 1.75 times higher, with a difference of 1.117 (95% CI 1.008 to 1.227). Net diversification, speciation minus extinction, was almost the same: 0.222 versus 0.188.
How they found it
Nobody can watch an extinct animal migrate, so the team built a predictor. In living species, migration correlates with body mass, the fraction of grass in the diet and where a species’ range sits in latitude. The authors used those correlations, plus the evolutionary tree, to score each extinct species. A score of 0.5 or higher counted as migratory, and a species counted if any of its populations made seasonal round trips.
They checked the method where they could. Fossil evidence for or against migration existed for 16 extinct species, and the prediction matched in 10 of them (63%). Six did not, which the authors link to differences between populations and to thin sampling.
Next came the models. HiSSE, short for hidden state speciation and extinction, estimates how fast lineages with and without a trait split and die out. The team ran it across 100 plausible tree shapes to reflect uncertainty about how species are related, once with fossil species and once with living species only.
Worked example: how big is the gap?
SciQuest calculation from the paper’s reported values. Extinct species: 41 ÷ 51 = 80.4%. Living species: 95 ÷ 207 = 45.9%. Rate ratios in the fossil-inclusive model: 2.825 ÷ 1.673 = 1.69 for speciation and 2.603 ÷ 1.486 = 1.75 for extinction. Checkable fossil matches: 10 ÷ 16 = 62.5%, which the paper reports as 63%.
Why it matters to you
Nothing here changes what you do this year. The practical link is to conservation. The authors argue that protecting migratory species deserves priority, because barriers, farming, overhunting and climate change are pressing on routes that animals depend on. The paper cites the saiga antelope, which fell by more than 95% after the Soviet Union’s collapse, and a wildebeest population in Kenya’s Athi-Kaputiei Plains that collapsed. Those are modern cases; the study asks whether the vulnerability runs deeper in time.
What the evidence does not show
It does not show that migration caused the extinctions. The analysis is correlational and phylogenetic, and the paper does not separate human hunting from climate change as the driver of the late Quaternary losses.
The result is also sensitive to modelling choices. With living species only, speciation and net diversification remained higher in migratory lineages, but extinction came out lower (0.013 versus 0.118). Extinction fraction, a related measure, pointed in different directions across tree versions. Whether fossils belong in such models is itself debated, and fossil sampling is uneven. The authors say they emphasise direction and consistency over exact values because magnitudes depend on model settings.
One further caution is SciQuest’s own reading, not a claim from the paper. Migration was predicted partly from body size and latitude, and the paper says the functional losses came from large-bodied, high-latitude migratory species. If the late Quaternary extinctions hit large animals hardest for reasons unrelated to migration, that could inflate the migratory share. The authors’ fossil check (10 of 16) is the main guard against it.
How this fits what we already knew
Modern work has documented falling migrations in many species, mostly tied to roads, fences, hunting, land-use change and climate. The new paper extends the question backward: many probably migratory large mammals vanished in the late Quaternary megafaunal extinctions, and the authors suggest the same pattern holds, in direction at least.
They also tested the loss of ecological roles. Removing the extinct species cut functional richness, a measure of the variety of traits in the community, by about 0.8% globally and about 2.7% in Africa. The global effect is small. Africa’s larger drop reflects the loss of large-bodied, high-latitude migratory species there.
Outside views and the authors’ interpretation
SciQuest has not interviewed an independent researcher and found no on-record outside comment yet. The only voices in the release are the authors’. Lead author Joel Abraham is quoted in the EurekAlert release speculating that “perhaps migration always enhances speciation, no matter the taxa!” That is a hypothesis about other animal groups, not a result of this study. The paper’s own funding came from US National Science Foundation and National Institutes of Health grants, and the authors declare no competing interests.
How other headlines framed it
- EurekAlert (PLOS release) stated the finding flatly: migrants are at greater risk of extinction.
- Phys.org reposted the release with a softer verb, “may be at greater risk,” closer to the paper’s own caution.
Both are the same source text, so there is no real spread of framing yet. The paper’s reversal in living-species-only models is not in either headline.
What happens next
The authors’ data and code are public on Dryad, so other teams can re-run the models with different tree sets, different ways of scoring migration, or different treatment of fossils. Direct fossil evidence of migration in more of the extinct species would test the imputed labels, since only 16 of 51 could be checked. For related reading on extinction risk and on how researchers piece together animals’ pasts, see our reports on reef-building corals and Caribbean barn owls.
In one sentence
Most recently extinct hooved mammals were probably migrants, and fossil-based models say migrants die out faster, but the link is correlational and the extinction-rate result reverses when extinct species are left out.
Quick check: did it click?
- What share of the 51 extinct ungulates were likely migratory, and how was that decided? About 80%, predicted from body mass, grass in the diet and latitude, and matched against fossil evidence in 10 of 16 testable species.
- Does the study prove migration causes extinction? No. It is a correlational model, and extinction rates flip direction when only living species are analysed.
Read next
- 44% of assessed reef-building corals are threatened: how extinction risk is measured at scale.
- Eland collagen in 60,000-year-old ochre: another hooved mammal’s trace in the Pleistocene record.
- Barn owls reached the Americas via the Caribbean: extinction on islands.
Sources and disclosure
- Abraham J.O., O’Brien K., Upham N.S., Jesmer B.R., Bibi F., Faith J.T. “Phylogenetic evidence that migratory behavior increases ungulate extinction rates.” PLOS Biology (2026). doi:10.1371/journal.pbio.3004072. Received 28 October 2025, accepted 8 October 2026, published 5 November 2026.
- PLOS release on EurekAlert, 5 November 2026: Hooved mammals that migrate are at greater risk of extinction than those that stay put.
- Data and code: Dryad dataset.
- Coverage read for framing: Phys.org (5 November 2026).
Disclosure: This article was drafted with AI assistance and checked against the sources above, including the paper’s open-access full text (SciQuest read the abstract, methods and results sections; the reference list was not read). Calculations by SciQuest: 41 ÷ 51 = 80.4%; 95 ÷ 207 = 45.9%; 2.825 ÷ 1.673 = 1.69; 2.603 ÷ 1.486 = 1.75; 10 ÷ 16 = 62.5%. The graphic is a SciQuest original built from the paper’s reported values. Spotted an error? See our corrections policy.
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